Hydraulic jack for camper bodies



1967 R. J. THURLOW, sR.. ETAL 3,350,063

HYDRAULIC JACK FOR CAMPER BODIES Filed Sept. 19, 1966 2 Sheets-Sheet 1INVENTOR. REGINALD J. THURLOW SR. REGINALD J. THURLOW Ill 2 Sheets-Sheet2 'I g I FIG.

INVENTOR. REGINALD J. THURLDW SR. REGINALD J. THURLDW l BY Oct 1967 R.J. THURLOW, SR, ETAL HYDRAULIC JACK FOR CAMPER BODIES Filed Sept. 19,1966 United States Patent 3,350,063 HYDRAULIC JACK FOR CAMPER BODIESReginald J. Thurlow, Sr., 685 26 Road, and Reginald J. Thurlow III, 685/2 26 Road, both of Grand Junction, Colo. 81501 Filed Sept. 19, 1966,Ser. No. 580,407 7 Claims. (Cl. 254-45) This invention relates tohydraulic lifting apparatus and, more specifically, to a retractableground supporting device carried on camper bodies and the like forloading and unloading the camper body into and out of the bed of apickup truck.

With the increased national popularity in outdoor recreation, the usageof coach or camper bodies mounted on trucks has become extensive. Theyprovide mobile compact living quarters and are highly regarded by bothsportsmen and vacationing families alike.

For the most, pickup trucks of this type are used for general utilitywhen not being used to haul a camper. The loading and removal of theseheavy camper bodies has always been a major problem. Various systems ofjacks and lifting devices have been developed, but have not provensatisfactory for various reasons. Some stationary systems have beendevised that are hung from garage rafters or other permanent structureswhich have obvious mobility limitations. One of the most prevalentmethods presently being used is a series of screw-type jacks, onemounted at each corner of the camper. It is not safe to raise or lower acamper unless there is a person at each jack so that the jacks are movedsimultaneously. Raising one corner at a time would also be damaging tothe lightweight structure of the camper body. Therefore, the necessityof four persons to operate the individual jacks limits the usefulness ofthe system.

The present invention provides a series of retractable hydraulic jacksmounted on the camper which are operated from a common power source. Thesystem is operated by a single person rather than one person at eachjack. By reason of the single power source, all four of the hydrauliccylinders can be raised simultaneously, thus avoiding theabove-mentioned problems. Since the lifting apparatus is carried on thecamper, its removal is not limited to a single location.

It is, therefore, the principal object of the present invention toprovide a novel and improved portable lifting device, in connection witha camper body to be loaded onto and unloaded from the bed of a pickuptruck.

A second object of the present invention is to provide a hydrauliclifting device including a series of hydraulic cylinders operatedsimultaneously by a single power source.

Another object of the present invention is the provision of a groundsupported lifting device for camper bodies which can be easily operatedby a single person.

Still another object of the present invention is to provide a portablelifting device which can be readily attached to or removed from a camperbody or various other types of truck mounted bodies.

An additional object of the invention is to provide an inexpensivelifting device which can be installed on all types of truck mountedcamper type coaches.

Further objects are to provide a lifting apparatus which can be safelyoperated by a single person with a minimum of time and effort.

Other objects will be in part apparent and in part pointed outspecifically hereinafter in connection with the description of thedrawings that follows, and in which:

FIGURE 1 is a right side elevational view of the camper suspended by itslifting jacks;

FIGURE 2 is a left side elevational view of the camper 3,350,063Patented Oct. 31, 1967 body suspended on its jacks with a pickup truckin loading position under the camper;

FIGURE 3 is a right side elevational view showing the camper mounted onthe truck and the lifting jacks pivoted into their retracted travelingposition;

FIGURE 4 is an enlarged fragmentary elevational view of the left forwardlifting cylinder and combined manifold and power source;

FIGURE 5 is a fragmentary section taken along line 55 of FIGURE 4; and

FIGURE 6 is a diagrammatic view of the hydraulic circuit and theassociated operating elements used with the structure disclosed inFIGURES 1 through 4.

Referring now to the drawings for a detailed description of the presentinvention, and initially to FIGURES 1 through 3 for this purpose, itwill be seen that the reference numeral 10 generally designates aconventional truck mounted coach, more popularly identified as a camper.The coach 10 includes a roof portion 12, a rear end 14 having a door(not shown in the drawings), side panels 15 and a front end portion 16which overhangs the cab 18 of the pickup truck. If the coach isconstructed for use as living quarters, a series of conventional windows20 are provided on the sides and ends thereof. Camper bodies of thistype are constructed so as to make full use of the overall interiordimensions of the truck body 22 as seen in FIGURE 2. While the width ofthe lower portion 24 of the camper is limited by the interior width ofthe truck body 22, the upper portion 26 extends outward over the sidewalls 28 of the truck to a maximum permissible road width for a truck ofthis type. Although there is a variety of different types and sizes ofcoach bodies which the present invention can be used with, the specificcoach body shown in FIGURES 1 to 3 is shown for purposes ofillustration.

In order to place the coach 10 in the truck bed and remove it from thebed, retractable ground engaging lifting apparatus generally designatedby numeral 30 are provided at each of the four corners of the coach 10.The lifting apparatus 30 comprises four hydraulic cylinders 32 which arepivotally attached to the side wall 26 of the coach by means of mountingplates 34. Integrally formed on the side of each cylinder 32 is apivotal mounting bolt 36 and corresponding nut 37 which allow thecylinder 32 to rotate from a horizontal retracted position to itsvertical operative position as seen in FIGURES 2 and 3.

The cylinders 34 are of a single action type having hydraulicconnections 38 located at the capend 40 of the cylinders. The mountingplates 34 are formed with a load supporting flange 42 along the loweredge thereof .as seen in FIGURE 4. The plates are attached to the sidewall 26 of the coach by a pair of bolts 44 and spacer washers 46, thelatter of which maintains the plates 34 and side wall 26 in spacedrelation. Located on the outer face of the mounting plates 34, in theplane of movement of the cylinders 32, is a pair limiting lugs or stops48. The lugs 48 are positioned so as to prevent rotary movement of thecylinders 32 in one direction from their vertical position. In viewingFIGURE 1, the lugs 48 on the cylinder located on the left side of thefigure prevent the cylinder from rotating in a clockwise direction pastthe vertical position. The lugs 48 on the right cylinder, in the samefigure, prevent the cylinder 32 from rotating in a counterclockwisedirection. The lugs do not prevent the respective cylinders 32 frombeing rotated in the opposite direction to their retracted positions asshown in FIGURE 3. The purpose of the lugs is to prevent anylongitudinal sway of the camper 10 while it is being supported on thejacks 32. For example, in FIGURE 1, if the camper would sway to theright, the lugs 48 on the left hand cylinder would restrain the camper,whereas the reverse movement would 58 is operating,

be limited by the lugs on the right hand cylinder 32. When the cylindersare not in use, they are rotated to the retracted traveling position andheld in place by brackets 50. Attached to outer extremity of the rodmember 52 of cylinder 32 is a bearing plate 54. The bearing plate 54 isof sufiicient size to carry the static load of the camper on normal soilwithout sinking in an appreciable amount.

The source of hydraulic pressure which supplies the four cylinders 32with their lifting force is derived from a hand-operated system 56 whichis carried on one of the mounting plates 34 as seen in FIGURE 4. Thepower source includes a hand-operated pump 58 supplied by a fluidreservoir 60 connected to the working cylinders 32 by means of amanifold 62 and series of hydraulic lines 640:, b, c and d. The pump 58is a single acting piston type which is operated by a pivoted hand lever66 which is in turn pivotally connected to the piston shaft 68.Connecting intake port 69 and the fluid reservoir 60 is an intake line72. Connecting the discharge port 70 and the distribution manifold 62 isa discharge line 74. Positioned in the intake line 72 is a check valve75 which prevents flow back into the reservoir. Located in the dischargeline 74 is an additional check valve 76 which prevents flow back intothe pump 58. When the pump fluid flows through the intake line 74 intothe manifold 62. The fluid in turn flows out each of the four connectinglines 64a, 64b, 64c and 64d to the respective cylinders 32a, 32b, 32cand 32d. Located in each of the connecting lines 64a, b, c and d,respectively, are four shutoff valves 78a, b, c, and d. By themanipulation of valves 78, various operations can be accomplished, forexample, certain pistons can be lowered while retaining others extendedor the converse. Once the cylinders 32 have been fully extended and itis desirous to retract same, valve 80 is opened allowing the fluid inthe cylinders 32 to flow back through manifold 62 and line 82 to thereservoir 60. Since the cylinders 32 are only single acting, they mustbe retracted by exerting an outside force on the individual piston rods52.

In briefly summarizing the operation of the lifting apparatus, thehydraulic jacks 32 are held in the retracted position by lockingbrackets 50 while the coach is being transported as seen in FIGURE 3. Toprevent any possible movement of the piston rods 52 while in transit,valves 78a, b, c and d can be closed, thereby preventing any fluid fromentering the cylinders 32. When it is desirous to remove the coach 10from the truck, the jacks 32 are released and pivoted downward to thevertical position shown in FIGURE 2. When the individual cylinder valves78a, b, c and d are opened, the weight of the piston rods 52 alone willextend the rods downward until the bearing plates 54 come in contactwith the ground. The uneven surface of the ground is compensated for bythe rods extending varying distances until contacting the ground. Thereturn valve 80 being closed, the coach 10 is ready to be lifted off thetruck body 22. As the pump 58 is activated by reciprocal movement ofhandle 66, fluid is introduced into manifold 62 which in turn flows intoeach cylinder 32. The cylinders 32 being exposed to equal pressure willbegin to extend, lifting the weight of the coach body off the truck. Aspreviously mentioned, the movement of each separate cylinder 32 can becontrolled by the individual shutoff valves 78a, b, c and d. Once thecoach is lifted a few inches off the truck bed, the truck can be drivenout from under the coach, leaving it supported on the jacks 32. Thecoach can be stored on the jacks 32 or, after the truck has beenremoved, it can be lowered onto rigid support objects placed thereunder.To reload the coach, the truck is merely backed into position and returnvalve 80 is opened, allowing the coach to settle back on the truck bed.

By reason of the simplified mounting structure, the lifting apparatus ofthe present invention can be easily adapted for use on any type ofunified load.

Having thus described the several useful and novel features incorporatedin the lifting apparatus of the present invention, it will be seen thatthe many worthwhile objectives for which it was designed have beenachieved. Although but a single specific embodiment and application ofthe lifting apparatus has been illustrated and described herein, werealize that certain changes may well occur to those skilled in the artwithin the broad teaching thereof; hence, it is our intention that thescope of the protection afforded hereby shall be limited only insofar assaid limitations are expressly set forth in the appended claims.

What is claimed is:

1. Lifting apparatus for loading and unloading a substantiallyrectangular coach body onto and off the bed of a pickup truck, saidapparatus comprising: four vertically positioned mounting plates adaptedto be releasably attached one at each corner of any type coach body, ahorizontal load supporting flange extending from the lower edge of saidplate and positioned to support the weight of the coach, fastening meansfor releasably attaching the mounting plates to the coach body; a seriesof four hydraulic cylinders having pistons with elongate portionsextending therefrom, ground supporting foot means located at the end ofthe elongate portions for transmitting the weight of the coach to theground; mounting means pivotally attaching each of said cylinders to arespective mounting plate for maintaining the cylinders in verticalground engaging position and upon retraction permitting the cylinders tobe pivoted to a horizontal position; bracket means attached to the coachbody for maintaining the cylinders in a horizontal position when liftingapparatus is not in use; and, a single hydraulic power means attached toone of said mounting plates, hydraulic lines connecting each of saidcylinders with said power means whereby all of said cylinders may beactivated in unison.

2. Lifting apparatus for loading and unloading a coach body onto and offof a pickup truck as defined in claim 1 in which; the mounting meansincludes one or more lugs attached to each of the mounting platesextending outward into the plane of movement of the cylinders wherebythe cylinders are maintained in a vertical load supporting position.

3. Lifting apparatus for loading and unloading a coach body onto and offof a pickup truck as defined in claim 1 in which: the mounting meansincludes an angular limit means attached to each of the mounting plateswhich maintains the cylinders in a vertical load supporting position,the limit means of the two cylinders positioned at the forward cornersof the coach permits the cylinders to be pivoted only in acounterclockwise direction from the vertical position, and the limitmeans of the two cylinders positioned at the rear corners of the coachpermits the cylinders to be pivoted only in a clockwise direction fromthe vertical position.

4. Lifting apparatus for loading and unloading a coach body onto and offof a pickup truck as defined in claim 1 in which: the mounting meansincludes a pivoting journal and bearing, a pair of lugs attached to eachof the mounting plates equi-distantly spaced from the axis of rotationof the cylinders extending outwardly into the plane of rotation of thecylinders on opposite sides thereof, the lugs on the two cylinders atthe forward end of the coach are positioned on respective sides of thecylinders to permit the cylinders to be pivoted only in acounterclockwise direction from the vertical position and the lugs onthe two cylinders positioned at the rear of the coach are positioned onopposite sides of the cylinders to permit the cylinders to be pivotedonly in a single direction from the vertical position.

5. Lifting apparatus for loading and unloading a coach body onto and offa pickup truck as defined in claim 1 in which: the power means includesa hand-operated hydraulic pump having a discharge port and an inletport, a manifold means connected to the discharge port of the pump, saidhydraulic lines connecting each of said cylinders to the manifold meanswhereby fluid entering the manifold is equally dispensed to theconnecting cylinders, a hydraulic reservoir connected to the inlet portof the pump and to the manifold means, and a first valve means locatedbetween the manifold and the reservoir whereby when open the cylindersare permitted to retract and the fluid allowed to flow back to thereservoir.

6. Lifting apparatus for loading and unloading a coach body onto and offof a pickup truck as defined in claim 1 in which: the power meansincludes a hand-operated single action hydraulic pump having dischargeand inlet ports, a manifold means connected to the discharge port, saidfirst hydraulic lines connecting each of said cylinders to the manifold,a hydraulic reservoir connecting to the inlet port of the pump to thereservoir, a second hydraulic line connecting the reservoir and themanifold, first valve means located in the second hydraulic line, andsecond valve means located in each of said first hydraulic lines wherebyactuation or retraction of one or more separate cylinders may beaccomplished independent of the remaining cylinders.

7. Lifting apparatus for loading and unloading a coach body onto and offof a pickup truck as defined in claim 1 in which: the fastening meansfor releasably attaching the mounting plates to the coach body include apair of mounting bolts and resilient means positioned between themounting plate and the side of the coach body.

References Cited UNITED STATES PATENTS 746,389 12/ 1903 Schmidt.2,023,336 12/1935 Moore et al. 25486 3,198,486 8/1965 Allen 254-453,243,193 3/1966 Fulmer et al. 25445 3,248,083 4/1966 De Geunaro et al.254-47 WILLIAM FELDMAN, Primary Examiner.

20 MILTON S. MEHR, Examiner.

1. LIFTING APPARATUS FOR LOADING AND UNLOADIG A SUBSTANTIALLYRECTANGUALR COACH BODY ONTO AND OFF THE BED OF A PICKUP TRUCK, SAIDAPPARATUS COMPRISING: FOUR VERTICALLY POSITIONED MOUNTING PLATES ADAPTEDTO BE RELEASABLY ATTACHED ONE AT EACH CORNER OF ANY TYPE COACH BODY, AHORIZONTAL LOAD SUPPORTING FLANGE EXTENDING FROM THE LOWER EDGE OF SAIDPLATE AND POSITIONED TO SUPPORT THE WEIGHT OF THE COACH, FASTENING MEANSFOR RELEASABLY ATTACHING THE MOUNTING PLATES TO THE COACH BODY; A SERIESOF FOUR HYDRAULIC CYLINDERS HAVING PISTONS WITH ELONGATE PORTIONSEXTENDING THEREFROM, GROUND SUPPORTING FOOT MEANS LOCATED AT THE END OFTHE ELONGATE PORTIONS FOR TRANSMITTING THE WEIGHT OF THE COACH TO THEGROUND; MOUNTING MEANS PIVOTALLY ATTACHING EACH OF SAID CYLINDERS TO ARESPECTIVE MOUNTING PLATE FOR MAINTAINING THE CYLINDERS IN VERTICALGROUND ENGAGING POSITION AND UPON RETRACTION PERMITTING THE CYLINDERS TOBE PIVOTED TO A HORIZONTAL POSITION; BRACKET MEANS ATTACHED TO THE COACHBODY FOR MAINTAINING THE CYLINDERS IN A HORIZONTAL POSITION WHEN LIFTINGAPPARATUS IS NOT IN USE; AND, A SINGLE HYDRAULIC POWER MEANS ATTACHED TOONE OF SAID MOUNTING PLATES, HYDRAULIC LINES CONNECTING EACH OF SAIDCYLINDERS WITH SAID POWER MEANS WHEREBY ALL OF SAID CYLINDERS MAY BEACTIVATED IN UNISON.